rockbox/firmware/kernel.c
Thom Johansen 52e91de5d3 First attempt at iPod threading.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7852 a1c6a512-1295-4272-9138-f99709370657
2005-11-13 23:47:38 +00:00

398 lines
8.7 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Björn Stenberg
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdlib.h>
#include <string.h>
#include "config.h"
#include "kernel.h"
#include "thread.h"
#include "cpu.h"
#include "system.h"
#include "panic.h"
#if (CONFIG_CPU != PP5020)
long current_tick = 0;
#endif
static void (*tick_funcs[MAX_NUM_TICK_TASKS])(void);
/* This array holds all queues that are initiated. It is used for broadcast. */
static struct event_queue *all_queues[32];
static int num_queues;
void sleep(int ticks) ICODE_ATTR;
void queue_wait(struct event_queue *q, struct event *ev) ICODE_ATTR;
/****************************************************************************
* Standard kernel stuff
****************************************************************************/
void kernel_init(void)
{
/* Init the threading API */
init_threads();
memset(tick_funcs, 0, sizeof(tick_funcs));
num_queues = 0;
memset(all_queues, 0, sizeof(all_queues));
tick_start(1000/HZ);
}
void sleep(int ticks)
{
/* Always sleep at least 1 tick */
int timeout = current_tick + ticks + 1;
while (TIME_BEFORE( current_tick, timeout )) {
sleep_thread();
}
wake_up_thread();
}
void yield(void)
{
switch_thread();
wake_up_thread();
}
/****************************************************************************
* Queue handling stuff
****************************************************************************/
void queue_init(struct event_queue *q)
{
q->read = 0;
q->write = 0;
/* Add it to the all_queues array */
all_queues[num_queues++] = q;
}
void queue_wait(struct event_queue *q, struct event *ev)
{
while(q->read == q->write)
{
sleep_thread();
}
wake_up_thread();
*ev = q->events[(q->read++) & QUEUE_LENGTH_MASK];
}
void queue_wait_w_tmo(struct event_queue *q, struct event *ev, int ticks)
{
unsigned int timeout = current_tick + ticks;
while(q->read == q->write && TIME_BEFORE( current_tick, timeout ))
{
sleep_thread();
}
wake_up_thread();
if(q->read != q->write)
{
*ev = q->events[(q->read++) & QUEUE_LENGTH_MASK];
}
else
{
ev->id = SYS_TIMEOUT;
}
}
void queue_post(struct event_queue *q, long id, void *data)
{
int wr;
int oldlevel;
oldlevel = set_irq_level(HIGHEST_IRQ_LEVEL);
wr = (q->write++) & QUEUE_LENGTH_MASK;
q->events[wr].id = id;
q->events[wr].data = data;
set_irq_level(oldlevel);
}
bool queue_empty(const struct event_queue* q)
{
return ( q->read == q->write );
}
void queue_clear(struct event_queue* q)
{
int oldlevel = set_irq_level(HIGHEST_IRQ_LEVEL);
q->read = 0;
q->write = 0;
set_irq_level(oldlevel);
}
int queue_broadcast(long id, void *data)
{
int i;
for(i = 0;i < num_queues;i++)
{
queue_post(all_queues[i], id, data);
}
return num_queues;
}
/****************************************************************************
* Timer tick
****************************************************************************/
#if CONFIG_CPU == SH7034
void tick_start(unsigned int interval_in_ms)
{
unsigned long count;
count = CPU_FREQ * interval_in_ms / 1000 / 8;
if(count > 0x10000)
{
panicf("Error! The tick interval is too long (%d ms)\n",
interval_in_ms);
return;
}
/* We are using timer 0 */
TSTR &= ~0x01; /* Stop the timer */
TSNC &= ~0x01; /* No synchronization */
TMDR &= ~0x01; /* Operate normally */
TCNT0 = 0; /* Start counting at 0 */
GRA0 = (unsigned short)(count - 1);
TCR0 = 0x23; /* Clear at GRA match, sysclock/8 */
/* Enable interrupt on level 1 */
IPRC = (IPRC & ~0x00f0) | 0x0010;
TSR0 &= ~0x01;
TIER0 = 0xf9; /* Enable GRA match interrupt */
TSTR |= 0x01; /* Start timer 1 */
}
void IMIA0(void) __attribute__ ((interrupt_handler));
void IMIA0(void)
{
int i;
/* Run through the list of tick tasks */
for(i = 0;i < MAX_NUM_TICK_TASKS;i++)
{
if(tick_funcs[i])
{
tick_funcs[i]();
}
}
current_tick++;
wake_up_thread();
TSR0 &= ~0x01;
}
#elif defined(CPU_COLDFIRE)
void tick_start(unsigned int interval_in_ms)
{
unsigned long count;
int prescale;
count = CPU_FREQ/2 * interval_in_ms / 1000 / 16;
if(count > 0x10000)
{
panicf("Error! The tick interval is too long (%d ms)\n",
interval_in_ms);
return;
}
prescale = cpu_frequency / CPU_FREQ;
/* Note: The prescaler is later adjusted on-the-fly on CPU frequency
changes within timer.c */
/* We are using timer 0 */
TRR0 = (unsigned short)(count - 1); /* The reference count */
TCN0 = 0; /* reset the timer */
TMR0 = 0x001d | ((unsigned short)(prescale - 1) << 8);
/* restart, CLK/16, enabled, prescaler */
TER0 = 0xff; /* Clear all events */
ICR1 = 0x8c; /* Interrupt on level 3.0 */
IMR &= ~0x200;
}
void TIMER0(void) __attribute__ ((interrupt_handler));
void TIMER0(void)
{
int i;
/* Run through the list of tick tasks */
for(i = 0;i < MAX_NUM_TICK_TASKS;i++)
{
if(tick_funcs[i])
{
tick_funcs[i]();
}
}
current_tick++;
wake_up_thread();
TER0 = 0xff; /* Clear all events */
}
#elif CONFIG_CPU == TCC730
void TIMER0(void)
{
int i;
/* Keep alive (?)
* If this is not done, power goes down when DC is unplugged.
*/
if (current_tick % 2 == 0)
P8 |= 1;
else
P8 &= ~1;
/* Run through the list of tick tasks */
for(i = 0;i < MAX_NUM_TICK_TASKS;i++)
{
if(tick_funcs[i])
{
tick_funcs[i]();
}
}
current_tick++;
wake_up_thread();
/* re-enable timer by clearing the counter */
TACON |= 0x80;
}
void tick_start(unsigned int interval_in_ms)
{
long count;
count = (long)FREQ * (long)interval_in_ms / 1000 / 16;
if(count > 0xffffL)
{
panicf("Error! The tick interval is too long (%dms->%lx)\n",
interval_in_ms, count);
return;
}
/* Use timer A */
TAPRE = 0x0;
TADATA = count;
TACON = 0x89;
/* counter clear; */
/* interval mode; */
/* TICS = F(osc) / 16 */
/* TCS = internal clock */
/* enable */
/* enable the interrupt */
interrupt_vector[2] = TIMER0;
IMR0 |= (1<<2);
}
#elif CONFIG_CPU == PP5020
void tick_start(unsigned int interval_in_ms) {
/* TODO: Implement tick_start */
(void)interval_in_ms;
}
#endif
int tick_add_task(void (*f)(void))
{
int i;
int oldlevel = set_irq_level(HIGHEST_IRQ_LEVEL);
/* Add a task if there is room */
for(i = 0;i < MAX_NUM_TICK_TASKS;i++)
{
if(tick_funcs[i] == NULL)
{
tick_funcs[i] = f;
set_irq_level(oldlevel);
return 0;
}
}
set_irq_level(oldlevel);
panicf("Error! tick_add_task(): out of tasks");
return -1;
}
int tick_remove_task(void (*f)(void))
{
int i;
int oldlevel = set_irq_level(HIGHEST_IRQ_LEVEL);
/* Remove a task if it is there */
for(i = 0;i < MAX_NUM_TICK_TASKS;i++)
{
if(tick_funcs[i] == f)
{
tick_funcs[i] = NULL;
set_irq_level(oldlevel);
return 0;
}
}
set_irq_level(oldlevel);
return -1;
}
#ifndef SIMULATOR
/*
* Simulator versions in uisimulator/SIMVER/
*/
/****************************************************************************
* Simple mutex functions
****************************************************************************/
void mutex_init(struct mutex *m)
{
m->locked = false;
}
void mutex_lock(struct mutex *m)
{
/* Wait until the lock is open... */
while(m->locked)
sleep_thread();
wake_up_thread();
/* ...and lock it */
m->locked = true;
}
void mutex_unlock(struct mutex *m)
{
m->locked = false;
}
#endif